Abstract

Direct-drive experiments at the University of Rochester's OMEGA laser [T. R. Boehly, R. L. McCrory, C. P. Verdon et al., Fusion Eng. Des. 44, 35 (1999)] have been performed to prototype eventual campaigns on the National Ignition Facility (NIF) [E. I. Moses and C. R. Wuest, Fusion Sci. Technol. 43, 420 (2003)] to investigate the mixing of target materials. Spherical-implosion targets with equatorial defects have been irradiated with polar direct drive, a requirement for direct-drive experiments at NIF. The physics question addressed by these results is whether simulations can match data on 0th-order hydrodynamics and implosion symmetry, the most basic implosion features, with and without the defect. The successful testing of hydrodynamic simulations leads to better designs for experiments and guides accurate planning for polar-direct-drive-ignition studies on the NIF platform.

The authors acknowledge the splendid support of Scott Evans, Tom Sedillo, Joe Cowan, Tom Archuleta, Joseph Katz, Julie Fooks, Vladimir Glebov, and the entire OMEGA laser operations crew. We thank Fred Marshall of LLE for his assistance with the laser pointing for polar direct drive. This work has been performed under the auspices of the United States Department of Energy, Contract No. DE-AC52-06NA25396.